Personality Research Corner

Personality Research Corner

Our personalities have a bearing on many aspects of our lives and well-being outside of work as well as in it. This occasional series of articles looks at some of the research that has been conducted to look at the association between personality and significant issues in our society.

Personality and obesity – is there a link?

With such a strong focus on obesity as a major public health crisis in the western world and beyond it is no surprise that significant research has been conducted into the relationship between personality and obesity. On the face of it, we might hypothesise that more Conscientious people will be better at sticking to a strict diet, for example. So those lower in Conscientiousness (Organisation in Quintax) might be expected to be more prone to being overweight or obese. And, of course, there is no shortage of stereotypical associations between obesity and personality in popular culture (e.g. ‘fat people are jolly’ suggests a link between Extraversion and obesity).

Working within the US’s National Institute of Health, Angelina Sutin and colleagues conducted a large scale, longitudinal study in which the relationship between measures of adiposity were examined in the context of Big Five personality for a sample of 1,988 Americans. The researchers looked at both the relationship between measures of adiposity and personality scores and the trajectory of weight change as a function of personality (uniquely the study had access to over 50 years of height and weight data for this sample).

The study categorised members of the sample in terms of their Body Mass Index (BMI) into normal-weight (BMI < 25), overweight (BMI = 25 – 30) and obese (BMI > 30). The researchers were able to find small, but significantly significant relationships between personality and adiposity (as measured by BMI) as follows:

Overweight and obese participants scored higher on Extraversion and Neuroticism (Quintax Emotional Involvement) than the normal-weight group

In Quintax terms, these findings suggest a small, but consistent trend for obese participants to be more Extravert, more Volatile and more Adaptable than the normal-weight comparison group. Overweight participants tend to be more Extravert, more Volatile, more Grounded Adaptable and more Logical than the normal-weight comparison group. What is more these relationships were found to hold for the trajectory of weight gain over time. That is, the more Extravert, Adaptable and Volatile participants showed a steeper increase in weight.

In their conclusions, the researchers placed most emphasis on the role of Neuroticism and Conscientiousness in relation to becoming overweight or obese. Specifically they draw on supporting research which suggests that those scoring high on Neuroticism and low on Conscientiousness are most likely to go through cycles of weight loss and weight gain as they embark on diet and lifestyle changes, but frequently relapse.

It must be emphasised that the relationships between personality and proneness to becoming overweight or obese are relatively small. We can’t simply state that everyone who is lower in Conscientiousness will become obese. Nor can obesity be seen as an inevitable consequence of having a particular personality style or combination of styles. While our personalities are relatively fixed, how we express them is open to our control. Perhaps the most useful conclusion to draw from this research is that we can potentially use personality assessment to identify how best to choose and tailor weight change interventions for individuals to maximise the possibility of them being successful.